1. Field of the Invention
This invention relates to a new and improved fitment having a removable membrane which closes off the interior of the fitment spout. More particularly, the invention relates to a fitment which fits around a hole in a panel of a paperboard carton or other container, used for packaging liquids and powders.
2. Description of Related Art
Fitments having membranes are shown in such patents as U.S. Pat. No. 5,303,838, issued Apr. 19, 1994, and particularly FIGS. 14-16 thereof. Other patents showing membranes are U.S. Pat. No. 3,458,080, issued Jul. 29, 1969, U.S. Pat. No. 4,380,303, issued Apr. 19, 1983, and others. The present invention is an improvement on the prior art in that in some modifications of the invention the membrane is located approximately midway of the height of the spout.
Other fitments are moved from a chute or other source to the interior of a carton by a spud which is attached to the fitment by vacuum. The present invention eliminates the use of vacuum and the mechanical problems inherent therein.
The fitment of the present invention comprises a spout portion having a peripheral flange which may be welded or otherwise attached to a panel of a paperboard carton or to a flexible plastic container. A spout projects upward from the flange and, in the preferred embodiments, is externally threaded adjacent its upper end. In some modifications of the invention, positioned within the spout is an internal membrane which may be concave and is joined to an inward projection of the spout along a line of weakness. A pull tab, such as a ring, is connected to the membrane in such fashion that by pulling the pull tab the membrane is detached from the inward projection of the spout. The concave membrane facilitates the consumer gripping the ring and has certain advantages in molding the part.
The cap of the present invention has a skirt which is internally threaded to engage the threads of the spout. A lower portion of the cap may have a tear band having a bead which snaps under a shoulder on the lower portion of the spout. The tear band may be connected to the upper portion of the skirt by frangible means so that the cap may not be removed without giving external evidence of tampering.
One of the features of the invention is the fact that the cap may be attached to the spout by pressing the cap downward relative to the spout, the mating threads on the spout and cap skirt slipping past each other and then interengaging. The tamper-evident band has a bead which engages a shoulder on the spout so that the cap cannot be unscrewed without severing the bridges which connect the band to the skirt and giving evidence of tampering.
The tear band not only provides tamper-evidencing in addition to the membrane being intact, it also is an anti-back-off feature to keep the cap from unscrewing during initial distribution.
A particular object and advantage of the present invention is that the fitment is so constructed that, by means of a spud of a mandrel, it may be moved from a chute or other storage location to the carton. In preferred embodiments the mandrel is moved to place the fitment inside the carton and maneuvered so that the spout fits through and extends outside a hole in a wall of the carton. In the prior art, the fitment has been held on the spud by vacuum. This method is undesirable in that a source of vacuum must be provided and, further, drawing the vacuum to a sufficient extent to hold the fitment on the spud is time consuming, as is release of the vacuum.
One means for attachment to the spud is to locate the membrane which seals the spout above the lower end of the spout a sufficient distance for the spud to enter the lower end of the fitment. One means for holding the fitment on the spud is to provide an internal bead near the bottom of the spout which frictionally engages the spud. In a modification of the present invention, such a bead is intermittent rather than continuous. In another version of the invention, vertical internal ribs are formed on the lower end of the spout to grip the spud.
In another modification of the invention, the membrane, if desired, may be positioned at or adjacent the lower end of the spout. A ring depending from fitment engages the exterior of the spud. Optionally, instead of a continuous ring, fingers may project below the flange engaging the exterior of the spud. Such fingers may be rectangular in cross section or hooked. In a further modification, the ring or fingers may engage a groove formed in the spud.
Another optional feature of the invention is to form the connector or post between the pull tab and the membrane of a resilient material and make it longer than the distance between the membrane and the upper end of the spout. With a cap applied to the spout, the pull tab bears against the underside of the top of the cap. When the cap is removed, the post straightens so that the pull tab pops above the upper edge of the spout, where it may be conveniently gripped by the consumer.
In a still further modification of the invention, a curvilinear tear line is formed on the membrane either on the top or bottom surface thereof which intersects the line of weakness between the membrane and the interior of the spout. The post connecting the membrane to the pull tab is preferably located at the intersection of the curvilinear line and the line of weakness. By pulling the pull tab, the membrane tears at the curvilinear line and also tears at the line of weakness, facilitating removal of the membrane.